CN108037359A - A kind of grid frequency measurement circuit for eliminating flickering and m-Acetyl chlorophosphonazo interference - Google Patents
A kind of grid frequency measurement circuit for eliminating flickering and m-Acetyl chlorophosphonazo interference Download PDFInfo
- Publication number
- CN108037359A CN108037359A CN201711165493.4A CN201711165493A CN108037359A CN 108037359 A CN108037359 A CN 108037359A CN 201711165493 A CN201711165493 A CN 201711165493A CN 108037359 A CN108037359 A CN 108037359A
- Authority
- CN
- China
- Prior art keywords
- resistance
- capacitance
- unit
- transport
- voltage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R23/00—Arrangements for measuring frequencies; Arrangements for analysing frequency spectra
- G01R23/02—Arrangements for measuring frequency, e.g. pulse repetition rate; Arrangements for measuring period of current or voltage
- G01R23/10—Arrangements for measuring frequency, e.g. pulse repetition rate; Arrangements for measuring period of current or voltage by converting frequency into a train of pulses, which are then counted, i.e. converting the signal into a square wave
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measurement Of Current Or Voltage (AREA)
- Measurement Of Resistance Or Impedance (AREA)
Abstract
The present invention proposes a kind of grid frequency measurement circuit for eliminating flickering and m-Acetyl chlorophosphonazo interference, and the measuring circuit includes voltage conversion unit, benchmark source unit, active power filtering unit, comparison circuit unit and Data Computation Unit；The voltage conversion unit is connected with active power filtering unit, and the active power filtering unit is connected with comparison circuit unit, and the comparison circuit unit is connected with Data Computation Unit, and the benchmark source unit is connected with the active power filtering unit and comparison circuit unit respectively.The present invention uses the form of hardware filtering, and the frequency information of power frequency both sides in power grid is filtered out, obtains stable analog signal, grid frequency value is obtained by average computation.The calculation amount of CPU can be greatly reduced, can also effectively eliminate m-Acetyl chlorophosphonazo, flickering influences.
Description
Technical field
It is more particularly to a kind of to eliminate flickering and m-Acetyl chlorophosphonazo the present invention relates to electric-power metering, intelligent meter metering and fields of measurement
The grid frequency measurement circuit of interference.
Background technology
Mains frequency is the important indicator of power quality, it is necessary to accurately measure, and mains frequency is also various power equipments
The important measurement data of safe and stable operation.Due to the diversity of electricity consumption facility, the complexity of network load change, often exists
The harmful effects such as flickering, harmonic wave and m-Acetyl chlorophosphonazo, the accuracy to grid frequency measurement are normal to power equipment there are considerable influence
Operation interferes, or destroys.Mains frequency be also calculate the power quality parameter such as flickering, harmonic wave and m-Acetyl chlorophosphonazo it is important according to
According to grid frequency measurement is inaccurate, power quality parameter can be caused to calculate inaccurate.Therefore, it is weight to measure accurate frequency values
Factor is wanted, the accurate measurement of frequency is also more and more of interest by people.
The prior art is by AD (analog-digital converter), gathers the analog signal of network voltage, gathered data is answered
Miscellaneous mathematical computations, and various software algorithm is used, complete frequency measurement.It can greatly increase the calculation amount of CPU, be applicable in ring
Also there is certain limitation in border.Existing hardware frequency measurement, grid frequency measurement is realized by zero cross detection circuit, it is humorous
Ripple, under the influence of flickering, can cause waveform pass zero point detection inaccurate, cause frequency measurement deviation.
The content of the invention
The present invention proposes a kind of mains frequency for eliminating flickering and m-Acetyl chlorophosphonazo interference to solve existing technical problem
Measuring circuit.
The purpose of the present invention is achieved through the following technical solutions：A kind of mains frequency survey for eliminating flickering and m-Acetyl chlorophosphonazo interference
Circuit is measured, the measuring circuit includes voltage conversion unit, benchmark source unit, active power filtering unit, comparison circuit unit sum number
According to computing unit；The voltage conversion unit is connected with active power filtering unit, the active power filtering unit and comparison circuit unit
Connection, the comparison circuit unit is connected with Data Computation Unit, the benchmark source unit respectively with the active power filtering unit
Connected with comparison circuit unit.
Further, the voltage conversion unit includes voltage-type voltage transformer and biasing circuit, a reference source list
Member includes a reference source voltage；Network voltage is converted to the identifiable voltage signal of system, institute by the voltage-type voltage transformer
The network voltage on the basis of GND that biasing circuit samples voltage-type voltage transformer is stated to be lifted to using a reference source voltage as base
It is accurate.
Further, the active power filtering unit is eight rank bandpass filters, and the eight ranks bandpass filter includes first
Transport and placing device and the second transport and placing device, the output signal output of the voltage conversion unit are transported to first transport and placing device, described first
The output signal for putting device is output to comparison circuit unit through the second transport and placing device.
Further, the eight ranks bandpass filter further include resistance R1, resistance R2, resistance R3, resistance R4, resistance R5,
Resistance R6, resistance R7, resistance R8, resistance R9, resistance R10, resistance R11, resistance R12, capacitance C1, capacitance C2, capacitance C3, capacitance
C4, capacitance C5, capacitance C6, capacitance C7 and capacitance C8；The output signal of voltage conversion unit is as the defeated of eight rank bandpass filters
The one end for entering signal with resistance R3 is connected, and the one end of the other end of resistance R3 respectively with resistance R5, capacitance C1 and capacitance C3 is connected,
The other end ground connection of the resistance R5, the one end of the other end of the capacitance C1 respectively with resistance R1 and resistance R4 is connected, described
The other end of capacitance C1 is also connected with the OUTA ports of the first transport and placing device, and the other end of the capacitance C3 is another with resistance R1
End connection is connected with-INA the ports of the first transport and placing device again, the other end of the resistance R4 respectively with resistance R6, capacitance C2 and electricity
Hold one end connection connection of C4, the other end ground connection of the resistance R6, the other end of the capacitance C4 distinguishes the one of connecting resistance R2
End and the-INB ports of the first transport and placing device, the OUTB ports of the first transport and placing device of another termination of the resistance R2, described first
The V- ports ground connection of transport and placing device, the V+ ports of first transport and placing device meet AVCC ,+INA the ports of first transport and placing device and+
INB ports meet a reference source voltage REF, and the other end of the resistance R2 is also connected with intermediate output BandPass4_8, the electricity
The other end for holding C2 is connected with intermediate output BandPass4_8, and intermediate output BandPass4_8 output signals are as input
Signal is connected with one end of resistance R9, and the one end of the other end of resistance R9 respectively with resistance R10, capacitance C6 and capacitance C7 is connected,
The other end ground connection of the resistance R10, the one end of the other end of the capacitance C6 respectively with resistance R7 and resistance R11 are connected, institute
The other end for stating capacitance C6 is also connected with the OUTA ports of the second transport and placing device, and the other end of the capacitance C7 is another with resistance R7
One end connection is connected with-INA the ports of the second transport and placing device again, the other end of the resistance R11 respectively with resistance R12, capacitance C5
Connected with one end of capacitance C8, the other end ground connection of the resistance R12, the one of the other end difference connecting resistance R8 of the capacitance C8
End and the-INB ports of the second transport and placing device, the OUTB ports of the second transport and placing device of another termination of the resistance R8, described second
The V- ports ground connection of transport and placing device, the V+ ports of second transport and placing device meet AVCC ,+INA the ports of second transport and placing device and+
INB ports meet a reference source voltage REF, and the other end of the resistance R8 is also connected with output terminal, the other end of the capacitance C5 with
Output terminal connects；The output terminal output voltage signal is to comparison circuit unit.
Further, resistance R1 and resistance the R2 values are 1M, the resistance R3, resistance R4, resistance R9 and resistance
R11 values are 240K, and resistance R5 and resistance the R6 values are 10K, and resistance R7 and resistance the R8 values are 1M5,
Resistance R10 and resistance the R12 values are 7K5, the capacitance C1, capacitance C2, capacitance C3, capacitance C4, capacitance C5 and capacitance
C8 values are 33nF, and capacitance C6 and capacitance the C7 values are 27nF.
Further, the comparison circuit unit is voltage comparator, and the voltage comparator is by an operational amplifier
Composition；The output signal of the active power filtering unit exports square-wave signal to Data Computation Unit through voltage comparator；The electricity
Source voltage on the basis of the reference voltage of pressure comparator.
Further, the Data Computation Unit is acquired square-wave signal, calculates the time of two rising edges of square wave
Difference, draws frequency by formula f=1/ △ t, measures mains frequency.
The present invention has following technological merit：
1st, the present invention uses the form of hardware filtering, eliminates the flickering in power grid and m-Acetyl chlorophosphonazo information, obtains the electricity of stabilization
Net frequency signal, mains frequency is obtained by average computation.M-Acetyl chlorophosphonazo, influence of the flickering to frequency measurement can be effectively eliminated.
2nd, hardware circuit filtering is relied only on, is not sampled by ADC, it becomes possible to obtains continuous, stable mains frequency letter
Number.Mains frequency is obtained by average computation.
3rd, mains frequency is obtained by average computation, without complicated algorithm, the calculation amount of CPU can be greatly reduced.
Brief description of the drawings
Fig. 1 is a kind of functional unit block diagram for the grid frequency measurement circuit for eliminating flickering and m-Acetyl chlorophosphonazo interference；
Fig. 2 is eight rank bandpass filter structures figures.
Embodiment
The technical solution in the embodiment of the present invention is carried out below in conjunction with the attached drawing in the embodiment of the present invention clear, complete
Ground describes, it is clear that described embodiment is only part of the embodiment of the present invention, instead of all the embodiments.Based on this
Embodiment in invention, the every other reality that those of ordinary skill in the art are obtained without making creative work
Example is applied, belongs to the scope of protection of the invention.
In order to improve frequency measurement accuracy, the interference of flickering and m-Acetyl chlorophosphonazo to frequency measurement is eliminated, reduces the calculating of CPU
Amount, the present invention propose a kind of grid frequency measurement circuit for eliminating flickering and m-Acetyl chlorophosphonazo interference.The circuit can be realized to power grid
The accurate measurement of frequency, eliminates flickering and the interference of m-Acetyl chlorophosphonazo.
With reference to Fig. 1, a kind of grid frequency measurement circuit for eliminating flickering and m-Acetyl chlorophosphonazo interference, the measuring circuit includes electricity
Press converting unit, benchmark source unit, active power filtering unit, comparison circuit unit and Data Computation Unit；The voltage conversion list
Member is connected with active power filtering unit, and the active power filtering unit is connected with comparison circuit unit, the comparison circuit unit and number
Connected according to computing unit, the benchmark source unit is connected with the active power filtering unit and comparison circuit unit respectively.
The voltage conversion unit includes voltage-type voltage transformer and biasing circuit, and the benchmark source unit includes benchmark
Source voltage；Network voltage (220V) is converted to the identifiable voltage signal of system (1.45V) by the voltage-type voltage transformer,
The network voltage on the basis of GND that the biasing circuit samples voltage-type voltage transformer be lifted to using a reference source voltage as
Benchmark.
With reference to Fig. 2, the active power filtering unit is eight rank bandpass filters, and the eight ranks bandpass filter includes the first fortune
Put device and the second transport and placing device, the output signal output of the voltage conversion unit to first transport and placing device, first amplifier
The output signal of device is output to comparison circuit unit through the second transport and placing device.The eight ranks bandpass filter filters voltage signal,
The interference of flickering m-Acetyl chlorophosphonazo is eliminated, exports stable voltage signal, its filter center frequency is 50Hz, and bandwidth -3dB is 8Hz,
Band resistance -40dB is 34Hz.First transport and placing device and the second transport and placing device select AD8657 or LM2904.
The eight ranks bandpass filter further includes resistance R1, resistance R2, resistance R3, resistance R4, resistance R5, resistance R6, electricity
Hinder R7, resistance R8, resistance R9, resistance R10, resistance R11, resistance R12, capacitance C1, capacitance C2, capacitance C3, capacitance C4, capacitance
C5, capacitance C6, capacitance C7 and capacitance C8；Voltage conversion unit output signal as eight rank bandpass filters input signal with
One end connection of resistance R3, the one end of the other end of resistance R3 respectively with resistance R5, capacitance C1 and capacitance C3 are connected, the resistance
The other end ground connection of R5, the one end of the other end of the capacitance C1 respectively with resistance R1 and resistance R4 are connected, the capacitance C1's
The other end is also connected with the OUTA ports of the first transport and placing device, the other end of the capacitance C3 be connected with the other end of resistance R1 and
Be connected with-INA the ports of the first transport and placing device, the other end of the resistance R4 respectively with resistance R6, capacitance C2 and capacitance C4 one
End connection connection, the other end ground connection of the resistance R6, one end of the other end difference connecting resistance R2 of the capacitance C4 and the
- INB the ports of one transport and placing device, the OUTB ports of the first transport and placing device of another termination of the resistance R2, first transport and placing device
V- ports are grounded, and the V+ ports of first transport and placing device meet AVCC, and+INA the ports and+INB ports of first transport and placing device connect
A reference source voltage REF, the other end of the resistance R2 are also connected with intermediate output BandPass4_8, and the capacitance C2's is another
One end is connected with intermediate output BandPass4_8, and intermediate output BandPass4_8 exports signal as input signal and electricity
One end connection of R9 is hindered, the one end of the other end of resistance R9 respectively with resistance R10, capacitance C6 and capacitance C7 is connected, the resistance
The other end ground connection of R10, the one end of the other end of the capacitance C6 respectively with resistance R7 and resistance R11 are connected, the capacitance C6
The other end be also connected with the OUTA ports of the second transport and placing device, the other end of the capacitance C7 is connected with the other end of resistance R7
Be connected again with the-INA ports of the second transport and placing device, the other end of the resistance R11 respectively with resistance R12, capacitance C5 and capacitance C8
One end connection, the other end ground connection of the resistance R12, one end of the other end difference connecting resistance R8 of the capacitance C8 and the
- INB the ports of two transport and placing devices, the OUTB ports of the second transport and placing device of another termination of the resistance R8, second transport and placing device
V- ports are grounded, and the V+ ports of second transport and placing device meet AVCC, and+INA the ports and+INB ports of second transport and placing device connect
A reference source voltage REF, the other end of the resistance R8 are also connected with output terminal, and the other end and the output terminal of the capacitance C5 connect
Connect；The output terminal output voltage signal is to comparison circuit unit.
Resistance R1 and resistance the R2 values are 1M, and the resistance R3, resistance R4, resistance R9 and resistance R11 values are equal
For 240K, resistance R5 and resistance the R6 values are 10K, and resistance R7 and resistance the R8 values are 1M5, the resistance
R10 and resistance R12 values are 7K5, and the capacitance C1, capacitance C2, capacitance C3, capacitance C4, capacitance C5 and capacitance C8 values are equal
For 33nF, capacitance C6 and capacitance the C7 values are 27nF.
The comparison circuit unit is voltage comparator, and the voltage comparator is made of an operational amplifier；It is described
The output signal of active power filtering unit exports square-wave signal to Data Computation Unit through voltage comparator；The voltage comparator
Source voltage on the basis of reference voltage.
The Data Computation Unit is acquired square-wave signal, calculates the time difference of two rising edges of square wave, passes through public affairs
Formula f=1/ △ t draw frequency, measure mains frequency.
The present invention uses the form of hardware filtering, and the frequency information of power frequency both sides in power grid is filtered out, obtains stable mould
Intend signal, grid frequency value is obtained by average computation.The calculation amount of CPU can be greatly reduced, can also effectively eliminate m-Acetyl chlorophosphonazo,
Flickering influences.
Above to a kind of grid frequency measurement circuit for eliminating flickering and m-Acetyl chlorophosphonazo interference provided by the present invention, carry out
It is discussed in detail, specific case used herein is set forth the principle of the present invention and embodiment, above example
Illustrate to be only intended to help the method and its core concept for understanding the present invention；Meanwhile for those of ordinary skill in the art, according to
According to the thought of the present invention, there will be changes in specific embodiments and applications, in conclusion this specification content
It should not be construed as limiting the invention.
Claims (7)
- A kind of 1. grid frequency measurement circuit for eliminating flickering and m-Acetyl chlorophosphonazo interference, it is characterised in that：The measuring circuit includes Voltage conversion unit, benchmark source unit, active power filtering unit, comparison circuit unit and Data Computation Unit；The voltage conversion Unit is connected with active power filtering unit, and the active power filtering unit is connected with comparison circuit unit, the comparison circuit unit with Data Computation Unit connects, and the benchmark source unit is connected with the active power filtering unit and comparison circuit unit respectively.
- 2. measuring circuit according to claim 1, it is characterised in that：It is mutual that the voltage conversion unit includes voltage-type voltage Sensor and biasing circuit, the benchmark source unit include a reference source voltage；The voltage-type voltage transformer turns network voltage It is changed to the identifiable voltage signal of system, the electricity on the basis of GND that the biasing circuit samples voltage-type voltage transformer Net voltage is lifted on the basis of a reference source voltage.
- 3. measuring circuit according to claim 2, it is characterised in that：The active power filtering unit is eight rank bandpass filterings Device, the eight ranks bandpass filter include the first transport and placing device and the second transport and placing device, and the output signal of the voltage conversion unit is defeated Go out to first transport and placing device, the output signal of first transport and placing device and be output to comparison circuit unit through the second transport and placing device.
- 4. measuring circuit according to claim 3, it is characterised in that：The eight ranks bandpass filter further include resistance R1, Resistance R2, resistance R3, resistance R4, resistance R5, resistance R6, resistance R7, resistance R8, resistance R9, resistance R10, resistance R11, resistance R12, capacitance C1, capacitance C2, capacitance C3, capacitance C4, capacitance C5, capacitance C6, capacitance C7 and capacitance C8；Voltage conversion unit it is defeated The input signal for going out signal as eight rank bandpass filters is connected with one end of resistance R3, the other end of resistance R3 respectively with resistance R5, capacitance C1 are connected with one end of capacitance C3, the other end of resistance R5 ground connection, the other end of the capacitance C1 respectively with electricity Resistance R1 is connected with one end of resistance R4, and the other end of the capacitance C1 is also connected with the OUTA ports of the first transport and placing device, the electricity The other end for holding C3 is connected with the other end of resistance R1 and is connected with-INA the ports of the first transport and placing device, and the resistance R4's is another One end is connected connection, the other end ground connection of the resistance R6, the capacitance with one end of resistance R6, capacitance C2 and capacitance C4 respectively One end of other end difference connecting resistance R2 and the-INB ports of the first transport and placing device of C4, another termination first of the resistance R2 The OUTB ports of transport and placing device, the V- ports ground connection of first transport and placing device, the V+ ports of first transport and placing device meet AVCC, described + INA the ports and+INB ports of first transport and placing device connect a reference source voltage (REF), and the other end of the resistance R2 is also defeated with centre Outlet (BandPass4_8) connects, and the other end of the capacitance C2 is connected with intermediate output (BandPass4_8), middle defeated Outlet (BandPass4_8) output signal is connected as input signal with one end of resistance R9, the other end of resistance R9 respectively with Resistance R10, capacitance C6 are connected with one end of capacitance C7, the other end ground connection of the resistance R10, the other end point of the capacitance C6 One end not with resistance R7 and resistance R11 is connected, and the other end of the capacitance C6 is also connected with the OUTA ports of the second transport and placing device, The other end of the capacitance C7 is connected with the other end of resistance R7 and is connected with-INA the ports of the second transport and placing device, the resistance The one end of the other end of R11 respectively with resistance R12, capacitance C5 and capacitance C8 is connected, the other end ground connection of the resistance R12, institute State one end of other end difference connecting resistance R8 and the-INB ports of the second transport and placing device of capacitance C8, the other end of the resistance R8 The OUTB ports of the second transport and placing device are connect, the V- ports ground connection of second transport and placing device, the V+ ports of second transport and placing device connect The AVCC ,+INA ports and+INB ports of second transport and placing device connect a reference source voltage (REF), and the other end of the resistance R8 is also It is connected with output terminal, the other end of the capacitance C5 is connected with output terminal；The output terminal output voltage signal is to comparison circuit Unit.
- 5. measuring circuit according to claim 4, it is characterised in that：Resistance R1 and resistance the R2 values are 1M, institute It is 240K to state resistance R3, resistance R4, resistance R9 and resistance R11 values, and resistance R5 and resistance the R6 values are 10K, institute It is 1M5 to state resistance R7 and resistance R8 values, and resistance R10 and resistance the R12 values are 7K5, the capacitance C1, capacitance C2, capacitance C3, capacitance C4, capacitance C5 and capacitance C8 values are 33nF, and capacitance C6 and capacitance the C7 values are 27nF.
- 6. measuring circuit according to claim 4, it is characterised in that：The comparison circuit unit is voltage comparator, institute Voltage comparator is stated to be made of an operational amplifier；The output signal of the active power filtering unit is through voltage comparator output side Ripple signal is to Data Computation Unit；Source voltage on the basis of the reference voltage of the voltage comparator.
- 7. measuring circuit according to claim 5, it is characterised in that：The Data Computation Unit adopts square-wave signal Collection, calculates the time difference of two rising edges of square wave, draws frequency by formula f=1/ △ t, measure mains frequency.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711165493.4A CN108037359B (en) | 2017-11-21 | 2017-11-21 | Power grid frequency measuring circuit for eliminating flicker and inter-harmonic interference |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711165493.4A CN108037359B (en) | 2017-11-21 | 2017-11-21 | Power grid frequency measuring circuit for eliminating flicker and inter-harmonic interference |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108037359A true CN108037359A (en) | 2018-05-15 |
| CN108037359B CN108037359B (en) | 2020-04-24 |
Family
ID=62094073
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711165493.4A Active CN108037359B (en) | 2017-11-21 | 2017-11-21 | Power grid frequency measuring circuit for eliminating flicker and inter-harmonic interference |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108037359B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109001504A (en) * | 2018-09-26 | 2018-12-14 | 西安理工大学 | A kind of same source device of generator frequency signal |
| CN109669070A (en) * | 2019-01-02 | 2019-04-23 | 中电和瑞科技有限公司 | A kind of frequency measurement method and frequency measurement circuit |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3813669A (en) * | 1972-03-27 | 1974-05-28 | Kidde & Co Walter | Frequency filter circuit apparatus |
| JPH06300793A (en) * | 1993-04-14 | 1994-10-28 | Pioneer Electron Corp | Fundamental frequency detecting method for ac signal |
| EP0527995B1 (en) * | 1991-03-06 | 1995-09-27 | Mesacon Gesellschaft für Messtechnik mbH | Electric circuit for measuring the frequency of laser doppler signals |
| CN201780304U (en) * | 2010-07-09 | 2011-03-30 | 洛阳市黄河软轴控制器有限公司 | Rotating speed measuring circuit of retarder |
| CN202563008U (en) * | 2012-05-04 | 2012-11-28 | 紫光测控有限公司 | Frequency measurement circuit |
| CN105116356A (en) * | 2015-09-27 | 2015-12-02 | 电子科技大学中山学院 | Magnetic field sensor |
| CN207198238U (en) * | 2017-09-04 | 2018-04-06 | 珠海格力电器股份有限公司 | Power grid frequency detection circuit |
-
2017
- 2017-11-21 CN CN201711165493.4A patent/CN108037359B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3813669A (en) * | 1972-03-27 | 1974-05-28 | Kidde & Co Walter | Frequency filter circuit apparatus |
| EP0527995B1 (en) * | 1991-03-06 | 1995-09-27 | Mesacon Gesellschaft für Messtechnik mbH | Electric circuit for measuring the frequency of laser doppler signals |
| JPH06300793A (en) * | 1993-04-14 | 1994-10-28 | Pioneer Electron Corp | Fundamental frequency detecting method for ac signal |
| CN201780304U (en) * | 2010-07-09 | 2011-03-30 | 洛阳市黄河软轴控制器有限公司 | Rotating speed measuring circuit of retarder |
| CN202563008U (en) * | 2012-05-04 | 2012-11-28 | 紫光测控有限公司 | Frequency measurement circuit |
| CN105116356A (en) * | 2015-09-27 | 2015-12-02 | 电子科技大学中山学院 | Magnetic field sensor |
| CN207198238U (en) * | 2017-09-04 | 2018-04-06 | 珠海格力电器股份有限公司 | Power grid frequency detection circuit |
Non-Patent Citations (1)
| Title |
|---|
| 肖朵艳 等: "一种实用的电力系统频率实时测量方法", 《电力系统保护与控制》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109001504A (en) * | 2018-09-26 | 2018-12-14 | 西安理工大学 | A kind of same source device of generator frequency signal |
| CN109001504B (en) * | 2018-09-26 | 2020-12-18 | 西安理工大学 | Generator frequency signal homologous device |
| CN109669070A (en) * | 2019-01-02 | 2019-04-23 | 中电和瑞科技有限公司 | A kind of frequency measurement method and frequency measurement circuit |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108037359B (en) | 2020-04-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104569902B (en) | Digital type electric energy meter power consumption measuring device and method | |
| CN105304303B (en) | A kind of accurate alterating and direct current current transformer | |
| CN110146201A (en) | A kind of transducing signal conditioning system and temperature-compensation method with temperature-compensating | |
| CN103852637B (en) | Intelligent electric meter with fundamental wave metering function and measurement method thereof | |
| CN104330681B (en) | Dc bus scurries into the detection means of exchange in a kind of DC power system | |
| CN108037359A (en) | A kind of grid frequency measurement circuit for eliminating flickering and m-Acetyl chlorophosphonazo interference | |
| CN205941680U (en) | Luo shi coil current mutual -inductor measuring device based on ancillary coil revises | |
| CN111398662A (en) | Current sensor for power transmission line | |
| CN104833297A (en) | Signal processing unit for multichannel micro-strain data acquisition system | |
| CN104407209A (en) | Energy efficiency metering detection method of distribution transformer | |
| CN111398645A (en) | Signal parameter detection device and method | |
| CN207399155U (en) | Signal filtering process Compare System based on analog-digital converter | |
| CN104391176A (en) | Software and hardware frequency measurement circuit compatible with electric power system signals | |
| CN105334386A (en) | Electric energy measuring system | |
| CN107843855A (en) | Accumulator internal resistance detecting system | |
| CN112526437A (en) | Real-time acquisition system for running state of high-voltage transformer group | |
| CN102901873A (en) | Device for measuring resistive current fundamental component of zinc oxide arrester | |
| CN102221643A (en) | Converter harmonic detector of direct current mine hoist | |
| CN212693881U (en) | Low-voltage switch cabinet power signal phase difference monitoring device | |
| CN211718374U (en) | Current detection circuit and current detection equipment | |
| CN212229025U (en) | Current sensor for power transmission line | |
| CN202159097U (en) | DC mine elevator current converter harmonic wave detection apparatus | |
| CN114113781A (en) | Frequency measuring circuit of power system | |
| CN205142149U (en) | Multichannel lock -in amplifier | |
| CN208477002U (en) | A kind of measurement protective device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |